Window shade

ABSTRACT

A window shade includes an upper track, a lower track, a shade assembly, a lift cord means and a bead chain means. The lift cord means includes two boxes located in the upper track at two sides thereof and a flattened cord winding on the periphery of a jutting ring located in each box. By coupling a transmission axle with a transmission means located at one side of the bead chain means a concurrent transmission can be formed. Thereby the bead chain can aid retraction of the shade assembly through the transmission means to reduce transmission load of the bead chain means. The bead chain means of a suitable loading capability can be selected according to the weight of the shade assembly to reduce the load of the transmission means to facilitate extension of the shade assembly.

FIELD OF THE INVENTION

The present invention relates to a window shade and particularly to a window shade movable through concurrent transmission of a lift cord means and a bead chain means to facilitate retraction or extension of a shade assembly.

BACKGROUND OF THE INVENTION

There are many different types of window shades on the market such as Venetian blinds, pleated window shades, roman shades and the like. They mainly aim to be installed at doors and windows of houses to block sunshine and serve decorative purpose. According to different user's requirements, the general window shades can be divided into one type which has a shade structure driven by a lift cord to control retraction and extension, and another type which has a longer window shade. When the longer window shade is retracted, the resulting size is larger, especially if the lift cord is a round one. The round lift cord tends to slip left and right after retraction. Moreover, moving stability of the lift cord for the longer window shade is not desirable. The longer the window shade, the greater imbalance occurs to the window shade. It becomes more difficult to control the movement of the longer window shade through the lift cord. Transmission load of the transmission means is greater. As a result, the lift cord and transmission means are prone to damage after a period of time. The lift span of the longer window shade suffers. Moreover, the transmission means of the longer window shade wears off easily, and has to be replaced frequently. Retraction or extension of the longer window shade also is more difficult. There are still rooms for improvement.

SUMMARY OF THE INVENTION

The present invention aims to provide a window shade to resolve the aforesaid problems of the conventional longer window shade that is more difficult to retract and causes too heavy of transmission load on the transmission means by providing a novel transmission means which incorporates a lift cord means and a bead chain means to generate concurrent transmission to facilitate retraction and extension of the window shade.

To achieve the foregoing object, the window shade of the invention mainly includes an upper track, a lower track, a shade assembly, a lift cord means and a bead chain means. The shade assembly is located between the upper track and the lower track that are spaced from each other. The lift cord means has two boxes located at two sides of the upper track and a flattened cord winding on the periphery of a jutting ring held in each box. By coupling a transmission axle with a transmission means located at one side of the bead chain means, the lift cord means and the bead chain means can be transmitted concurrently.

The window shade thus constructed can achieve the following benefits: 1. during retraction of the window shade, the bead chain of the bead chain means drives the transmission means, so that the lift cord means and the bead chain means transmit concurrently. With the aid of the bead chain means, the lift cord means can extend or retract the shade assembly easier, and transmission load of the bead chain means can be reduced; 2. when the retracted longer window shade is to be lowered and extended, the weight of the shade assembly which is much greater than the bead chain means can reduce the transmission load of the transmission means. Hence the power needed to extend the longer window chain can be reduced.

The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of the invention.

FIG. 2 is a perspective view of the invention.

FIG. 3 is an exploded view of the lift cord means of the invention.

FIG. 4 is an exploded view of the bead chain means of the invention.

FIG. 5 is a side view of the bead chain means in a transmission condition.

FIG. 6 is a schematic side view of the shade assembly and lift cord means of the invention in an extended condition the flattened cord stretched.

FIG. 7 is an exploded view of another embodiment of the bead chain means of the invention.

FIG. 8 is a schematic side view of the bead chain means in a use condition according to FIG. 7.

FIG. 9 is an exploded view of yet another embodiment of the bead chain means of the invention.

FIG. 10 is a schematic side view of the bead chain means in a transmission condition according to FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 1 and 2, a window shade according to the invention mainly includes an upper track 10, a lower track 20, a shade assembly 30, a lift cord means 40 and a bead chain means 50.

The upper track 10 is hollow and elongate, and has openings 11 and 12 at two ends to be wedged in respectively by an anchor seat 13, and has a first latch hole 14 and a second latch hole 15 and a trough 16 at the bottom thereof.

The lower track 20 is elongate and spaced from the upper track 10 at a lower side, and has a wedge trough 21 and openings 22 and 23 at two ends to be wedged in by edge sealing elements 24 corresponding to the wedge trough 21.

The shade assembly 30 is located between the upper track 10 and the lower track 20, and includes a slat 31 which may be a beehive slat, a Venetian blind slat assembly or pleated blind slat assembly. In the embodiment shown in the drawings, the slat 31 is a beehive slat with an upper end and a lower end forming respectively a first wedge plate 32 and a second wedge plate 33 to be wedged respectively in a trough 16 of the upper track 10 and the wedge trough 21 of the lower track 20, and to be coupled with the upper track 10 and the lower track 20. The first and second wedge plates 32 and 33 and slat assembly 30 have respectively apertures 321, 331 and 311 corresponding to the first and second latch holes 14 and 15 of the upper track 10.

Also referring to FIGS. 3 and 6, the lift cord means 40 is located in the upper track 10 and run through by two sides of a transmission axle 45, and has two elastic latch elements 414 at the bottom to be wedged in the first and second latch holes 14 and 15 for anchoring. It mainly includes a box 41 and a lid 42 coupling with each other, a jutting ring 43 located in the box 41, and a flattened cord 44 winding on the periphery of the jutting ring 43. The flattened cord 44 has a latch element 441 at one end to be anchored on the jutting ring 43.

The box 41 has a housing chamber 410 at one side, a first opening 411 at a bottom end and a recess 412 on the periphery, and latch cavities 413 formed at the corners thereof, and with two corresponding elastic latch members 414 extended from the bottom thereof to be wedged in the first and second latch holes 14 and 15 of the upper track 10. There is a threading slot 415 formed between the two elastic latch elements 414. The lid 42 is formed in a shape mating the box 41 to cover the housing chamber 410, and has a latch flange 421 wedging in the recess 412, and tenons 422 wedging in the corresponding latch cavities 413. It also has a second opening 423 at one end corresponding to the first opening 411. The jutting ring 43 is held in the housing chamber 410 of the box 41, and has an inner round strut 431 and an outer annular ring 432. The inner round strut 431 has a hinge hole 4311 in the center corresponding to the first opening 411 on the box 41 and the second opening 423 on the lid 42. The outer annular ring 432 has a latch slot 4321 on the periphery to be wedged in by the latch element 441 at one end of the flattened cord 44 for anchoring so that the other end of the flattened cord 44 can be wound on the outer peripheral surface of the outer annular ring 432. Finally, the other end of the flattened cord is threaded through the apertures 321, 311 and 331 of the first wedge plate 32, slat 31 and second wedge plate 33, and fastened to the bottom of the second wedge plate 33.

Also referring to FIG. 1, there are anchor elements 46 with an axle hole 461 formed thereon disposed at two ends of the lift cord means 40 and run through by the transmission axle 45. The axle hole 461 has a screw hole 462 to be fastened by a fastening element 463 such as a screw to anchor the lift cord means 40 at two sides and prevent the lift cord means 40 from moving to the left and right on the transmission axle 45.

Referring to FIGS. 1, 4 and 5, the bead chain means 50 is wedged in the opening 12 of the upper track 10, and includes a first box 51, a second box 52 and a transmission means 53 hinged in the first box 51 and the second box 52.

The first box 51 has a first wedge flange 511 and apertures 512 on the periphery. The first wedge flange 511 is wedged in the opening 12 of the upper track 10, and has a strut 514 with a housing trough 513 and a coupling hole 5131 formed at the front end thereof, and a second wedge flange 515 on another side with a wedge trough 516 formed on the periphery thereof.

The second box 52 is formed in a shape mating the first box 51, and has a housing compartment 521 with an opening at a lower side to cover the first box 51. The housing compartment 521 has a strut 522 and a flattened strut 523 corresponding to and latching on the aperture 512 and second wedge flange 515. The housing compartment 521 further has a coupling hub 524 corresponding to the housing trough 513.

The transmission means 53 includes at least:

a hollow barrel 531 made of metal to be coupled with the inner rim of the housing trough 513 of the strut 514;

an elastic element 54 which is coupled on an inner lower side of the barrel 531, and has two ends forming a first lug 541 and a second lug 542;

a hollow coupling ring 55 coupling on an inner upper portion of the barrel 531 above the elastic element 54;

a movable element 56 which has a round stem 561 coupling with the coupling hole 5131 of the first box 51. The round stem 561 has a first axle hole 562 at one end to be wedged by the other end of the transmission axle 45, and an arched strut 563 at a distal end that has two planes 564 to latch the first and second lugs 541 and 542 of the elastic element 54 to form rotary coupling;

a hinge element 57 which has a flange 571 and an arched strut 572 at one side. The flange 571 is coupled with the housing trough 513 of the first box 51, and the arched strut 572 is inserted in the coupling ring 55 corresponding to the arched strut 563. The arched strut 572 has a second axle hole 573 formed on another side;

a bead chain 58 formed by stringing a plurality of beads 581 in an equal interval; and

a rotary element 59 which has a plurality of notches 591 formed on the periphery to hold the beads 581, and is held in the housing compartment 521 of the second box 52, and has a stub shaft 592 to be coupled with the second axle hole 573 of the arched strut 572, and a cavity 593 at another side opposing the second axle hole 573 to be coupled with the coupling hub 524 of the second box 52.

When in use and the shade assembly 30 is to be extended, pull manually the bead chain 58 of the bead chain means 50, the beads 581 drive the rotary element 59 to turn counterclockwise, and the transmission axle 45 turns concurrently to drive the flattened cord 44 at two sides of the lift cord means 40 to stretch; meanwhile, the slat 31 of the shade assembly 30 also is extended (referring to FIG. 6). By contrast, pull manually the bead chain means 50 to turn. clockwise, the beads 581 drives the rotary element 59 to turn clockwise, and the transmission axle 45 is turned concurrently to drive the flattened cord 44 in a retracting condition, and the slat 31 is retracted.

Refer to FIGS. 7 and 8 for another embodiment of the invention. In this embodiment, the housing compartment 521 a of the second box 52 a has an inclined guiding trough 520 a covered by the first box 51 a which has an inclined wedge element 510 a. Therefore, the beads 581 of the bead chain 58 can slide along the guiding trough 520 a to the front end of the bead chain means 50 a to facilitate moving operation of the bead chain 58.

When the invention is in use for a lengthy and heavier window shade, referring to FIGS. 9 and 10, a bead chain means 60 of a suitable loading capability to mate the weight of the lengthy window shade is selected, and a gear set 64 is provided and hinged on one side of the transmission means 63 at one side of the first and second boxes 61 and 62. The gear set 64 has a first gear 641 and a plurality of second gears 642 engaged on the periphery thereof. The second gears 642 are engaged with teeth 651 formed on a coupling member 65 at one side of the first box 61. Thus a concurrent transmission can be formed. As a result, two lift cord means (not shown in the drawings) can perform retraction with the aid of the bead chain means 60 to effectively reduce the transmission load of the transmission means 63. To extend the retracted shade assembly (not shown in the drawings) of a lengthy window shade downwards, the transmission load of the transmission axle (not shown in the drawings) also can be reduced through the aid of the bead chain means 60 of the suitable loading capability set forth above. 

1. A window shade, comprising: a hollow and elongate upper track which has openings at two ends wedged respectively by an anchor seat and a first latch hole, a second latch hole and a trough formed at the bottom thereof; an elongate lower track which is spaced from the upper track at a lower side and has a wedge trough and openings at two ends thereof wedged respectively by an edge sealing element corresponding to the wedge trough; a shade assembly which is located between the upper track and the lower track and has a beehive slat which has an upper end and a lower end formed respectively a first wedge plate and a second wedge plate to wedge respectively in the trough of the upper track and the wedge trough of the lower track to connect to the upper track and the lower track; a lift cord means which is located in the upper track and run through by two sides of a transmission axle, and includes a box and a lid coupling with each other, a jutting ring located in the box and a flattened cord winding on the periphery of the jutting ring that has a latch element at one end latching on the jutting ring; the box having two corresponding elastic latch elements extended from the bottom thereof to wedge in the first latch hole and the second latch hole for anchoring and a threading slot between the two elastic latch elements to be threaded through by the flattened cord; and a bead chain means located on the opening of another side of the upper track and includes a first box and a second box that are coupled together and a transmission means hinged in the first box and the second box; the transmission means including at least a barrel, an elastic element held in an inner lower half portion of the barrel that has two ends formed respectively a first lug and a second lug corresponding to each other, a coupling ring held in an inner upper half portion of the barrel above the elastic element, a movable element which has one end coupling with the first box, a hinge element held in the first box, a bead chain driving the transmission means and a rotary element located in the second box and wound by the bead chain.
 2. The window shade of claim 1, wherein the slat is selectively a beehive slat, a Venetian blind slat assembly or a pleated blind slat assembly.
 3. The window shade of claim 1, wherein the first wedge plate, the second wedge plate and the shade assembly have respectively an aperture corresponding to the first latch hole and the second latch hole of the upper track.
 4. The window shade of claim 1, wherein the box has a housing chamber at one side, a first opening at the bottom end of the housing chamber, a recess formed on the periphery and a latch cavity at each of corners thereof.
 5. The window shade of claim 1, wherein the lid has a latch flange on the periphery, a second opening on one end and a tenon at each of corners thereof.
 6. The window shade of claim 1, wherein the jutting ring is located in the box and has an inner round strut and an outer annular ring, the inner round strut having a hinge hole in the center, the outer annular ring having a latch slot formed on the periphery thereof.
 7. The window shade of claim 1, wherein the lift cord means has two ends coupled respectively with an anchor element which has an axle hole formed thereon to be fastened to the transmission axle to prevent the lift cord means from moving to a left side and a right side.
 8. The window shade of claim 1, wherein the first box has a first wedge flange and coupling holes on the periphery of one side, a strut which has a housing trough and a coupling hole at a front end thereof, and a second wedge flange on the periphery of another side thereof.
 9. The window shade of claim 1, wherein the second box has a housing compartment at one side that has a strut and a flattened strut and a coupling hub above the housing compartment.
 10. The window shade of claim 9, wherein the housing compartment has an inclined guiding trough.
 11. The window shade of claim 1, wherein the movable element has a round stem at one end that has a first axle hole and an arched strut extended from a distal end thereof, the arched strut having two ends formed respectively a plane.
 12. The window shade of claim 1, wherein the hinge element has an annular flange and an arched strut at one side, the arched strut having a second axle hole on another side.
 13. The window shade of claim 1, wherein the rotary element has a plurality of notches on the periphery, a stub shaft extended from one side and a cavity formed on another side thereof.
 14. The window shade of claim 1, wherein the bead chain means has a gear set pivotally coupled on one side of the transmission means located at one side of the first box and the second box.
 15. The window shade of claim 14, wherein the gear set has a first gear and a plurality of second gears that are engaged with each other, the second gears being engaged with teeth formed on a coupling member at one side of the first box to form concurrent transmission. 